Disclosed are intermediate transfer members, and more specifically, intermediate transfer members selected for the transfer of developed images in for example, an electrostatographic, for example xerographic, including digital, image on image, and the like, machines or apparatuses, and printers, inclusive of office printers, production printers, and the like. In embodiments, there are selected intermediate transfer members comprised of a polymer blend of a polymethacrylimide (PMMI) and a polysulfone (PSU), a polymethacrylimide and a polyphenylsulfone (PPSU), or a polymethacrylimide and a polyethersulfone (PESU), which individual polymers are commercially available. In embodiments thereof, the polymer blend of a polymethacrylimide and a polysulfone, a polymethacrylimide and a polyphenylsulfone, or a polymethacrylimide and a polyethersulfone are dispersed in or mixed with a conductive component such as a carbon black and a suitable solvent, such as N-methylpyrrolidinone (NMP), N,N′-dimethylformamide (DMF), or N,N′-dimethylacetaimide (DMAc), and subsequently the resulting dispersion is subjected to known casting methods, to form the intermediate transfer member. Also, in embodiments, the polymer blend of a polymethacrylimide and a polysulfone, a polymethacrylimide and a polyphenylsulfone, or a polymethacrylimide and a polyethersulfone together with a carbon black are extruded by a known extrusion device to form the intermediate transfer members or the intermediate transfer members can be generated by known solution casting processes.
A number of advantages are associated with the intermediate transfer members, such as belts (ITB) of the present disclosure such as excellent toner transfer efficiency, for example from about 90 to about 95 percent of the developed image can be transferred from the ITB to a substrate, like paper; functional resistivity, excellent modulus, and excellent break strength; an acceptable thermal expansion coefficient (CTE) and an acceptable hygroscopic expansion coefficient (CHE); wear and abrasion resistance; and low and acceptable surface friction characteristics for aiding in the transfer of developed xerographic images.
In electrostatographic printing machines wherein the toner image is electrostatically transferred by a potential difference between the imaging member and the intermediate transfer member, the transfer of the toner particles to the intermediate transfer member and the retention thereof should be substantially complete so that the image ultimately transferred to the image receiving substrate will have a high resolution. Substantially about 100 percent toner transfer occurs when most or all of the toner particles comprising the image are transferred, and little residual toner remains on the surface from which the image was transferred.
Intermediate transfer members may possess a number of advantages, such as enabling high throughput at modest process speeds; improving registration of the final color toner image in color systems using synchronous development of one or more component colors and using one or more transfer stations; and increasing the number of substrates that can be selected. However, a disadvantage of using an intermediate transfer member is that a plurality of transfer operations is usually needed allowing for the possibility of charge exchange occurring between toner particles and the transfer member which ultimately can lead to less than complete toner transfer, resulting in low resolution images on the image receiving substrate, and image deterioration. When the image is in color, the image can additionally suffer from color shifting and color deterioration.
In a typical electrostatographic reproducing apparatus, such as xerographic copiers, printers, multifunctional machines, and the like a light image of an original to be copied is recorded in the form of an electrostatic latent image upon a photosensitive member or a photoconductor, and the latent image is subsequently rendered visible by the application of electroscopic thermoplastic resin particles and colorant. Generally, the electrostatic latent image is developed by contacting it with a developer mixture comprised of carrier granules having toner particles adhering triboelectrically thereto, or a liquid developer material, which may include a liquid carrier having toner particles dispersed therein. The developer mixture is advanced into contact with the electrostatic latent image, and the toner particles are deposited thereon in image configuration. Subsequently, the developed image is transferred to a document, such as paper and fixed or fused by for example heat and pressure. It is advantageous in some instances to transfer the developed image to a intermediate transfer web, belt or component, and subsequently, transfer with a high, for example about 90 to about 100, transfer efficiency the developed image from the intermediate transfer member to a substrate, like paper, cardboard, transparencies, and the like.
It has been reported in several U.S. patents that intermediate transfer members enable acceptable registration of the final color toner image in color systems using synchronous development of one or more component colors, and using one or more transfer stations; and all for an increase the number of substrates that can be selected. However, a disadvantage of using an intermediate transfer member is that a plurality of developed toner transfer operations is utilized thus causing charge exchange between the toner particles and the transfer member, which ultimately can cause less than complete toner transfer, resulting in low resolution images on the image receiving substrate, like paper, and image deterioration. When the image is in color, the image can additionally suffer from color shifting and color deterioration.
In embodiments, it is desired to provide an intermediate transfer member, which has excellent transfer capabilities, for example, as compared to an intermediate transfer member where a polymer blend of a polymethacrylimide and a polysulfone, a polymethacrylimide and a polyphenylsulfone, or a polymethacrylimide and a polyethersulfone is absent; and possesses excellent release properties from a metal substrate permitting manufacturing simplicity. It is also desired to provide a weldable intermediate transfer belt that may not, but could, have puzzle cut seams, and instead, has a weldable seam, thereby providing a belt that can be manufactured without labor intensive steps, such as manually piecing together the puzzle cut seam with fingers, and without the lengthy high temperature and high humidity conditioning steps. It is also desired to provide an intermediate transfer member, which has excellent wear and abrasion resistance, and more specifically, has excellent mechanical properties as compared, for example, to an intermediate transfer member where a polymer blend of a polymethacrylimide and a polysulfone, a polymethacrylimide and a polyphenylsulfone, or a polymethacrylimide and a polyethersulfone are absent.